Trioxyanthraquinone dye.



UNITED STATES Patented October 18, 1904.

PATENT OFFICE.

LUDWIG WOLMAN, OF ELBERFELD, GERMANY, ASSIGNOR TO FARBEN- FABRIKEN OF ELBERFELD 00., OF NEW YORK, N. Y., A CORPORATION or NEW YORK.

TRIOXYANTHRAQUINONE DYE.

SPECIFICATION forming part of Letters Patent No. 772,857, dated October 18, 1904.

Application filed August 18, 1904. Serial No. 221,291. (No Specimens-l in New Anthracene Dye; and I hereby declare the following to be a clear and exact description of my invention.

' My invention relates to the manufacture of the hitherto-unknown 1.2.5-trioxyanthraq uinone having the formula which according to my researches can be obtained by the action of fuming sulfuric acid or sulfuric acid anhydrid and boric acid upon .alizarin. The process is to be stopped when the formation of the above-mentioned trioxyanthraquinone is terminated and before a further oxidation takes place. At first a sulfuric-acid ester 'is produced,which can be transformed into the 1.2.5-trioxyanthraquinone by saponification. a

In order to carry out my invention practically, I can proceed as follows, the parts being by weight: In an iron vessel provided with a stirrer twelve parts of boric acid (previously dried at 100 centigrade) are dissolved in one thousand. parts of fuming sulfuric acid, (eighty per cent. ofSO and eighty parts of dry alizarin are then introduced into the resulting solution at a temperature of about from 30 to 35. centigrad e. The mixture is stirred at this temperature for from eighteen to thirty-six hours until a test portion when saponified and then dissolved in sulfuric acid shows a reddish-violet color. Subsequently the reaction mass is diluted 'by the addition of one to 274E Centigrade;

thousand parts of sulfuric acid of Baum, and the resulting mixture is poured into water. The reddish-brown precipitate thus obtained is filtered off and dissolved in hot diluted caustic-soda lye. This solution is then decomposed by the addition of dilute hydrochloric acid on heating the mass for some time to boiling, and the precipitate thus obtained is then filtered OH and washed. A yel-' lowish-orange paste is thus obtained, representing a yellowish-orange powder after be' ing dried. By a recrystallization from glacial acetic acid the new body is obtained in the shape of red needles, melting at from 273 By treatment with acetic anhydrid it is transformed into the triacetylized derivative, producing yellow needles having a melting-point of 227 to 228 centigrade. The new 1.2.5-trioxyanthraquinone thus produced is soluble in concentrated sulfuric acid with a reddish-violet color turning blue by the addition of boric acid and soluble in caustic-soda lye with a reddish-violet color, being not essentially changed by the further addition of caustic-soda lye. It dissolves in an alcoholic solution of sodium hydroXid with a blue color, this solution showing a characteristic spectrum, (three bands in orange, yellow, and green.) It dyes alumina-mordanted cotton pure bluish-red and chrome-mordanted cotton bluish-violet shades.

Having now described my invention and in what manner the same is to be performed, what I claim as new, and desire to secure by Letters Patent, is

The herein-described new 1.2. 5-trioxyanthraquinone which represents red needles solution of caustic-soda lye With a blue color, I In testimony \vhercofl have signed myimme this solutlon showlng a characteristic spec- 1n the presence of two subscribing witnesses.

trum having three bands 1n orange, yellow and green; and dyeing alumina-mordanted LUDW'HT 5 cotton pure bluish-red and chrome-mordanted \Vitncsses:

cotton bluish-violet shades, substantially as O'r'ro KONIG, hereinbefore described. J. A. RrrrrnusimUs. 

